diff --git a/CHANGELOG.md b/CHANGELOG.md
index 30988889..1758cb4f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@
 
 ### Bugs fixed
 
+* [#645](https://github.com/clojure-emacs/clojure-mode/issues/645): Fix infinite loop when sorting a ns with comments in the end.
 * [#586](https://github.com/clojure-emacs/clojure-mode/issues/586): Fix infinite loop when opening file containing `comment` with `clojure-toplevel-inside-comment-form` set to `t`.
 
 ## 5.16.0 (2022-12-14)
diff --git a/clojure-mode.el b/clojure-mode.el
index 320eca1c..aac6c8b2 100644
--- a/clojure-mode.el
+++ b/clojure-mode.el
@@ -2030,7 +2030,13 @@ content) are considered part of the preceding sexp."
   (save-restriction
     (narrow-to-region (point) (save-excursion
                                 (up-list)
-                                (1- (point))))
+                                ;; Ignore any comments in the end before sorting
+                                (backward-char)
+                                (forward-sexp -1)
+                                (clojure-forward-logical-sexp)
+                                (unless (looking-at-p ")")
+                                  (search-forward-regexp "$"))
+                                (point)))
     (skip-chars-forward "\r\n[:blank:]")
     (sort-subr nil
                (lambda () (skip-chars-forward "\r\n[:blank:]"))
diff --git a/test/clojure-mode-util-test.el b/test/clojure-mode-util-test.el
index bf17d02a..353f0e5e 100644
--- a/test/clojure-mode-util-test.el
+++ b/test/clojure-mode-util-test.el
@@ -136,7 +136,49 @@
       (expect (buffer-string) :to-equal
               "(ns my-app.core
     (:require [my-app.views [user-page :as user-page]]
-              [rum.core :as rum] ;comment\n))")))
+              [rum.core :as rum] ;comment
+))")))
+
+  (it "should sort requires in a basic ns with comments in the end"
+    (with-clojure-buffer "(ns my-app.core
+    (:require [rum.core :as rum] ;comment
+              [my-app.views [user-page :as user-page]]
+              ;;[comment2]
+))"
+      (clojure-sort-ns)
+      (expect (buffer-string) :to-equal
+              "(ns my-app.core
+    (:require [my-app.views [user-page :as user-page]]
+              [rum.core :as rum] ;comment
+
+              ;;[comment2]
+))")))
+  (it "should sort requires in ns with copyright disclamer and comments"
+   (with-clojure-buffer ";; Copyright (c) John Doe. All rights reserved.
+;; The use and distribution terms for this software are covered by the
+;; Eclipse Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)
+(ns clojure.core
+  (:require
+   ;; The first comment
+   [foo] ;; foo comment
+   ;; Middle comment
+   [bar] ;; bar comment
+   ;; A last comment
+   ))"
+      (clojure-sort-ns)
+      (expect (buffer-string) :to-equal
+              ";; Copyright (c) John Doe. All rights reserved.
+;; The use and distribution terms for this software are covered by the
+;; Eclipse Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)
+(ns clojure.core
+  (:require
+   ;; Middle comment
+   [bar] ;; bar comment
+   ;; The first comment
+   [foo] ;; foo comment
+
+   ;; A last comment
+   ))")))
 
   (it "should also sort imports in a ns"
     (with-clojure-buffer "\n(ns my-app.core